A computing system may include a number of memory modules. These memory modules may serve as system memory or “primary memory” of the system, which may store information for running programs and the like. These memory modules may serve also, in some situations, serve as “secondary memory” or longer term storage, to store information of the system, even after power cycles. Some memory modules include at least one volatile memory (i.e., memory cell) and at least one non-volatile memory (i.e., memory cell).